Preoccupied with the tasks imposed upon him by his ego and the European psyche, overburdened by the obligation to produce, averse to diversion, and no lover of the external world and its variety, he was quite content with the view of the earth's surface that anyone can gain without stirring far from home, and never so much as tempted to venture beyond Europe. Especially now that his life was on the decline and his fear of failing to achieve his artistic goals—the concern that his time might run out before he had accomplished what he needed to accomplish and given fully of himself—could no longer be dismissed as a caprice, he had confined his external existence almost exclusively to the beautiful city that had become his home and the rustic cottage he had built for himself in the mountains and where he spent the rainy summers. (1.7)
Does Aschenbach have a midlife crisis or what? One of Aschenbach's motivations for wanting to escape to Venice is his experience of writers' block. But there's more to it than that, and this passage makes clear that Aschenbach's change, from never even feeling "tempted to venture beyond Europe" to longing for the exotic, has something to do with the realization of his own mortality—his fear, "that his life was on the decline and his fear of failing to achieve his artistic goals." What else is writer's block than the death of writing?
There was nothing stirring behind the stonemasons' fences, where crosses, headstones, and monuments for sale formed a second, uninhabited graveyard, and the mortuary's Byzantine structure opposite stood silent in the glow of the waning day. Its façade, decorated with Greek crosses and brightly hued hieratic patterns, also displayed a selection of symmetrically arranged gilt-lettered inscriptions concerning the afterlife, such as "They Enter into the Dwelling Place of the Lord" or May the Light Everlasting Shine upon Them," and reading the formulas, letting his mind's eye lose itself in the mysticism emanating from them, served to distract the waiting man for several minutes until, resurfacing from his reveries, he noticed a figure in the portico above the two apocalyptic beasts guarding the staircase, and something slight out of the ordinary in the figure's appearance gave his thoughts an entirely new turn. (1.3)
Remember this guy Aschenbach meets in the graveyard? Well, suffice it to say that encountering this strange-looking fellow is what inspires Aschenbach to travel. Of course, it's also significant that he meets this guy in a graveyard, with "Greek crosses" (foreshadowing later references to ancient Greece) and various Christian inscriptions about death. Mortality is there from the very beginning.
His motto was Durchhalten, "Persevere," and he regarded his Frederick-the-Great novel as nothing short of the apotheosis of this command, which he considered the essence of a cardinal virtue: action in the face of suffering. Then, too, he ardently desired to live to old age, for he had always believed that the only artistic gift that can be called truly great, all-encompassing, and, yes, truly praiseworthy is one that has been vouchsafed productivity at all stages of human existence. (2.4)
When it comes to writing, we already know that Aschenbach is one tough cookie. At the beginning of Death in Venice, his life is defined by a philosophy of perseverance, which informs his understanding of writing as a kind of heroic duty. But even this "action in the face of suffering" has something to do with a fear of death—his "ardent desire to live to old age" seems to mask his fear of losing his artistic productivity.
Once Aschenbach had had a closer look, however, he realized with something akin to horror that the man was no youth. He was old, there was no doubting it: he had wrinkles around his eyes and mouth; the matt crimson of his cheeks was rouge; the brown hair beneath the straw hat with its colorful band—a toupee; the neck—scrawny, emaciated; the stuck-on mustache and imperial on his chin—dyed; the full complement of yellow teeth—a cheap denture; and the hands, with signet rings on both forefingers, those of an old man. A shudder ran through Aschenbach as he watched him and his interplay with his friends. Did they not know, could they not see that he was old, that he had no right to be wearing their foppish, gaudy clothes, no right to be carrying on as if he were one of them? (3.4)
What's important here is the way the description of this character's old age draws attention to his mortality, his aging body that has "no right" to be parading about in a young man's outfit. In this way, too, this guy foreshadows Aschenbach's own fate, making us wonder what Aschenbach's infatuation with Tadzio has to do with holding onto youth and fearing death.
He drooled, he squinted, he licked the corners of his mouth, and the dyed imperial on his old man's chin jutted into the air. "Our compliments," he babbled on, placing two fingers to his lips, "to your sweetheart, your sweet, your most beautiful sweetheart…" And suddenly the upper denture slipped out of his jaw over the lover lip. Aschenbach managed to escape. "Your sweetheart, your lovely sweetheart," came the cooing, hollow, garbled words behind him as he made his way down the gangplank, clutching the rope railing. (3.12)
This guy is just… yuck. Why is he here? Well, Aschenbach wonders the same thing, but as it turns out, this old guy on the boat to Venice reminds us of what Aschenbach himself will become. In his old age, sexuality—and this guy seems to be making a sexual advance of some sort—only becomes a reminder of mortality, symbolized here by the dentures that fall out of the man's mouth as he tries to give his "compliments" to Aschenbach's "sweetheart."
He had noticed, however, that Tadzio's teeth were less than attractive: a bit jagged and pale, lacking the gleam of health, and with that brittle, transparent quality sometimes found in anemic. He is very frail, he is sickly, thought Aschenbach. He'll probably not live long. And he made no attempt to account for why he felt satisfied or consoled at the thought. (3.62)
Tadzio's beauty is made all the more fleeting because it comes with signs of death. Aschenbach notices early on that Tadzio appears sick, with bad-looking teeth (reminding us of the dentures worn by the old man on the boat), and feels consoled. Is this because he doesn't want Tadzio to grow older, or, for Aschenbach, does beauty have some other connection to death?
The recipient of this smile hurried off with it as if it were a fatal gift. He was so shaken that he felt compelled to flee the light of the terrace and front garden and hastily sought the obscurity of the rear grounds. […]Leaning back, arms dangling, overwhelmed and shuddering repeatedly, he whispered the standard formula of longing—impossible here, absurd, perverse, ridiculous and sacred nonetheless, yes, still venerable even here: "I love you!" (4.20)
Let's talk about Tadzio's "fatal gift." With a single smile, seeming to acknowledge Aschenbach's attention, Aschenbach is thrown into quite a frenzy, which ends with him admitting to himself that he loves Tadzio. In this case, the possibility of Tadzio reciprocating means Aschenbach acknowledges that his desires for Tadzio are sexual, and not just an artist's appreciation for his beautiful form. What might that realization have to do with mortality?
Such was Venice, the wheedling, shady beauty, a city half fairy tale, half tourist trap, in whose foul air the arts had once flourished luxuriantly and which had inspired musicians with undulating, lullingly licentious harmonies. The adventurer felt his eyes drinking in its voluptuousness, his ears being wooed by its melodies; he recalled, too, that the city was diseased and as concealing it out of cupidity, and the look with which he peered out after the gondola floating ahead of him grew more wanton. (5.9)
Death in Venice isn't the best travel guide. In this novella, the city embodies Aschenbach's own decline, appearing on the one hand as a symbol of European civilization, and on the other becoming diseased and trying to conceal it. The city, like Aschenbach, is portrayed as a dying entity.
In the general commotion and confusion he ventured a glance in Tadzio's direction and, as he did so, noticed that when returning the glance the boy was equally grave, as if he were modeling his conduct and facial expression on Aschenbach's and the general mood had no hold upon him because Aschenbach remained aloof from it. There was something at once disarming and overwhelming in this telling, childlike obedience; it was all the elderly man could do to keep from burying his face in his hands. He also had the feeling that Tadzio's tendency to pull himself up and take deep breaths was the sign of a constricted chest. "He is sickly and has probably not long to live," he thought with the objectivity that strangely enough breaks free on occasion from intoxication and longing, and his heart swelled with pure concern and a concomitant profligate satisfaction. (5.28)
Here, we get another reference to Tadzio's mortality. It's interesting to not that Aschenbach's observation of Tadzio's mortality becomes a moment of "objectivity" that "breaks free […] from intoxication." Aschenbach can be objective when it comes to thinking about Tadzio's death, but is it maybe his own death that he's thinking about instead?
There had been an hourglass in his parents' house many years before, and all at once he could see the fragile yet momentous little device as if it were standing before him. The rust-colored sand would run soundless and fine through the narrow glass neck, and when the upper bulb was nearly empty a small raging whirlpool would form there.
Sometimes we all need a good, old-fashioned metaphor. This image of Aschenbach's parents' hourglass, with the sand that runs round and round before forming a "small raging whirlpool" at the end, perfectly captures Aschenbach's own life: stoic discipline that continues on and on, before, at the end of it all, a "raging" passion takes it all down.